The present invention relates to a cooling device for an automotive battery having at least one coolant line and at least one separate pressing element, which is designed with elasticity, to press the coolant line against an exterior side, preferably a flat side of the automotive battery. The present invention also relates to an automotive battery module having such a cooling device as well as a method for manufacturing such a cooling device.
A generic cooling device is known from US 2011/132580, for example. The pressing element is a tension frame made of metal, which is bolted to the coolant line and presses an electrical element of the automotive battery against the coolant line by means of a spring element. Such pressing elements have a high weight and require a complex mounting on the automotive battery, in particular in a case when a plurality of electrical elements must be used. Moreover, the metal tension frame may function as a heat bridge and thus reduce the effective cooling power of the cooling device in this way.
The object of the invention is to create a cooling device of a low weight and a pressing element, which has good and long-lasting elastic properties and can be manufactured easily and inexpensively.
This and other objects are achieved according to the invention by a cooling device for an automotive battery, comprising at least one coolant line and at least one separate pressing element, which is designed to be elastic, to press the coolant line against an exterior side, preferably a flat side of the automotive battery. The pressing element is designed as a composite component, which has a separately manufactured reinforcing component that is enclosed in plastic material. The weight of the cooling device and its manufacturing cost can be reduced due to the use of plastic material. On the one hand, the composite design with the reinforcing component permits improved mechanical properties, in particular with respect to stability, elasticity and long service life. Due to the design as a composite component with a reinforcing component manufactured separately, a long-lasting pressing element can be produced by simple manufacturing methods, for example, such as sheathing the reinforcing component. The plastic material of the pressing element makes it possible to design the pressing element with a low thermal conductivity in particular.
According to the preferred specific embodiment, the coolant line is in direct contact with the battery.
The plastic material enclosing the reinforcing component has a lower thermal conductivity than the reinforcing component in particular. This prevents unwanted transfer of heat with the cooling device.
A particularly long-lasting and compact reinforcing component can be implemented because the reinforcing component is made of metal.
For example, the metal reinforcing component may be sheet metal, which preferably has a curved shape in the relaxed state. Sheet metal can be manufactured easily in a variety of shapes by punching and shaping.
To achieve long-lasting elastic properties of the pressing element, the metal reinforcing component may be an elastic metal component, preferably made of spring steel or an elastic aluminum alloy.
It is possible that the pressing element has at least one elastic leg formed by the reinforcing components enclosed in the plastic material. Two elastic sections are preferably provided, each forming one leg of the pressing element.
A low structural height and good spring properties can be achieved by designing the elastic leg with a shallow angle to the cooled outside of the automotive battery. For example, the elastic leg may be positioned at an angle of less than 45°.
The elastic legs may have regions with a heterogeneous resistance torque to induce a more uniform deformation of the elastic section under load. Thus a local overloading of the elastic legs is prevented and the lifetime of the pressing element is extended.
To form regions with a different resistance moment, the reinforcing component may be designed heterogeneously, for example, with respect to its cross-sectional shape, and/or regions where the plastic sheathing is of a different thickness may be provided. This permits an equalization to develop between different load zones and preferably also permits a uniform deformation under load on the pressing element.
The pressing element may have at least one receptacle section, which receives the coolant line. The receptacle section permits positioning of the coolant line in particular as well as good pressing against the exterior side of the automotive battery that is to be cooled. The receptacle section may preferably permit mounting of the coolant line on the pressing element in a preassembled state.
The coolant line is preferably designed to be flat and to have a top side that is essentially complementary to the adjacent exterior side of the automotive battery, such that the cross section of the coolant line has a width that is preferably greater than its height. The largest possible area of direct contact between the coolant line and the exterior side of the automotive battery is provided in this way, so that no separate heat transfer element is needed between the coolant line and the automotive battery.
For example, between 35% and 70% of the cooled exterior side of the automotive battery may be contacted by coolant lines.
Improved insulation of the cooled exterior side of the battery may be implemented when at least one thermal insulation component, which is connected to the pressing element and forms insulation for the cooled exterior side of the battery, is provided.
An automotive battery module according to the invention comprises an automotive battery, which includes at least one battery element and the cooling device mentioned above, such that the cooling device is disposed between a flat side of the battery element that is to be cooled and a housing of the automotive battery, and the at least one coolant line is in direct contact with the flat side of the battery element that is to be cooled. This arrangement permits a compact design of the cooling device. Furthermore, the pressing element of the cooling device permits equalization of the tolerance between the housing of the automotive battery and the flat side of the battery elements to be cooled.
Simple positioning of the cooling device in the automotive battery module is made possible, in that the housing of the automotive battery has recesses and/or protrusions, which cause the cooling device, in particular the pressing elements, to be positioned relative to the housing.
A method according to the invention for manufacturing a cooling device for an automotive battery with an exterior side to be cooled comprises the process steps: providing a reinforcing component, in particular an elastic metal component; manufacturing an elastic pressing element as a composite component by sheathing the reinforcing component with a plastic material; and mounting a coolant line of the composite component, wherein the composite component is acted upon toward the coolant line in deformation at a right angle to the exterior side of the automotive battery that is to be cooled. The battery in particular has a planar exterior side to be cooled.
The reinforcing component may be punched from sheet metal and preferably shaped into a curved shape.
A simple and inexpensive manufacturing method is made possible by producing the composite part by extrusion, wherein the reinforcing component is sheathed with plastic material using an extrusion die.
To ensure good bonding of the plastic material to the reinforcing component, the reinforcing component may be coated with a primer layer prior to bonding to the plastic material.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of one or more preferred embodiments when considered in conjunction with the accompanying drawings.